Some portable devices, such as cellular phones and music players, have the capabilities of data communications, such as Internet access through wireless wide area networks over cellular telecommunication networks, or through wireless local area networks. For example, a portable device may have web browsers to display web pages and thus allow users to perform searches via various search engines accessible through the web browsers.
Some portable devices have keyboards to receive input from the user. The keyboards may include a set of hardware buttons arranged in a layout similar to a conventional keyboard, or a display of an image of a keyboard on a touch screen, which allows users to select the keys from the graphical display on the touch screen.
Some portable devices also provide voice-based user interfaces. For example, the user may use voice commands to dial a phone number on a cellular phone, or to submit a search request.
Some portable devices may switch between a landscape mode and a portrait mode for the display of content on a display screen, based on the orientation of the portable device. For example, when a user holds a cellular phone in a vertical direction, the portable device presents the content on the display screen in a portrait mode; and when the user holds the cellular phone in a horizontal direction, the portable device presents the content on the display screen in a landscape mode.